The mode of nutrition in plants is different from animals, plants have a pigment known as chlorophyll to synthesize food, while animals, fungi, and other bacteria depend on other organisms for food.
The word 'autotroph' comes from two Greek words: 'autos' (meaning self) and 'trophe' (meaning nutrition). In autotrophic nutrition, an organism creates its own food from basic raw materials.
Green plants are autotrophs, meaning they can make their own food through photosynthesis. Photosynthesis is a process where plants, algae, and some bacteria use chlorophyll, water, and carbon dioxide to make glucose and release oxygen with the help of sunlight. The equation of photosynthesis is:
6 + 6 + light energy →
+ 6
carbon dioxide () and water (), with the help of light energy, are converted into glucose () and oxygen ().
The term "heterotroph" comes from the Greek words "heteros" meaning "other" and "trophe" meaning "nutrition". Heterotrophic organisms get their food from other organisms, unlike autotrophs which can make their own food. Heterotrophs are sometimes called consumers because they rely on other organisms for their food. This category includes animals, non-green plants, and fungi.
Consumers who consume herbs and other plants are called herbivores
Consumers who consume animals are called carnivores
Depending on the mode of living and the mode of intake of food, heterotrophs may be parasitic, saprotrophic, or holozoic
Parasitic nutrition: Parasites are organisms that live on or inside other living beings, called hosts. They get their food from the host, but the host does not get benefit from them. This is called parasitic nutrition.
Examples: few examples of parasites are Cuscuta (a plant parasite), hookworms, tapeworms, leeches, etc.
Saprotrophic nutrition: Saprotrophs are organisms that get their food from dead and decaying organic material. This way of getting food is called saprotrophic nutrition. They release enzymes that break down complex food into simple forms.
Examples: few examples of saprotrophs are fungi and bacteria
Holozoic nutrition: In holozoic nutrition, complex organic substances are taken in and not broken down immediately. Instead, enzymes produced by the organism digest the food after it's been ingested. The digested food is then absorbed by the body, while the undigested waste is expelled. Examples: holozoic nutrition is mainly found in non-parasitic animals, including simple ones like Amoeba and complex ones like humans.
Amoeba identifies their food.
Amoeba throws out small pseudopodia (false feet) that enclose the food particle and prevent it from escaping.
The enclosed food forms a food vacuole within the cell membrane.
Digestive enzymes produced by lysosomes break down complex food into simpler molecules.
The digested food is distributed in the cytoplasm.
Undigested waste is expelled from the cell membrane.
Paramecium is a unicellular organism with a specific shape.
Food is ingested through a special opening called the cytostome, which is like a cell mouth.
Cilia (hair-like structures) that cover the entire surface of the cell bring food to the cytostome opening.
The lashing movement of the cilia helps to move the food toward the cytostome.
Once the food reaches the cytostome, it is ingested into the cell.
Plants need minerals for their growth and development. The process of getting these minerals and using them is called mineral nutrition. During this process, plants absorb minerals from the soil, distribute them to the different parts of the plant, and use them to grow and develop. This helps the plant to stay healthy and strong.
Plants need both macronutrients and micronutrients, more macronutrients are required by the plants than micronutrients
Essential plant nutrients are mentioned in the following chart
Nitrogen is a critical element for plants.
Plants need nitrogen to synthesize amino acids, which are the building blocks for proteins.
Nitrogen is also required for the production of chlorophyll, the pigment that helps plants absorb sunlight and convert it into energy through photosynthesis.
Additionally, nitrogen is necessary for the production of nucleic acids, which are the genetic material that contains instructions for growth and development in plants.
Enzymes, which are the catalysts for many metabolic reactions in plants, also require nitrogen.
Out of all the metabolic elements that plants get from the soil, nitrogen is needed in the largest amounts.
Symptoms of nitrogen deficiency
Without sufficient nitrogen, plants can suffer from pale leaves, reduced growth, and decreased productivity.
Magnesium is an essential element for plants.
Many enzymes in plant cells require magnesium to function properly.
Magnesium is also a constituent of the chlorophyll molecule, which is the pigment that gives plants their green color and is critical for photosynthesis.
Symptoms of magnesium deficiency
Magnesium deficiency is a common problem in plants.
It is most prevalent in sandy-textured soils, which are subject to leaching.
Leaching is when water carries nutrients away from the soil and out of the root zone, making them unavailable to the plant.
Magnesium deficiency is more likely to occur during seasons of excess rainfall and leaching is more likely to happen.
The main symptom of magnesium deficiency is interveinal chlorosis, which means that the veins of the leaves stay green, but the areas between them turn yellow.
The bottom leaves are typically the first to be affected by magnesium deficiency.
